Diary of a medical scientist

medicineisnotmerchandise: Rheumatic Fever: ASCHOFF BODY Aschoff...

Sun, 16 Jun 2013 09:36:24 +0100

Rheumatic Fever: ASCHOFF BODY

Aschoff bodies are granulomatous structures consisting of fibrinoid change, lymphocytic infiltration, and characteristically abnormal macrophages surrounding necrotic centres. Some of these macrophages may fuse to form multinucleated giant cells.

In this picture a well-circumscribed lesion is demonstrated in the interstitium of the myocardium. The area of central necrosis is surrounded by a ring of plump histiocytes called Anitschkow or “caterpillar cells”.

medicalschool: Illustration of the Human Heart

Sun, 16 Jun 2013 04:48:39 +0100

medicalschool:

Illustration of the Human Heart

manicpixiedreamqueer: The Bielschowsky stain is a technique...

Sat, 15 Jun 2013 19:12:28 +0100

manicpixiedreamqueer:

The Bielschowsky stain is a technique used in neruopathology that stains certain types of nerve cells with silver nitrate.

image source: http://www.pathology.vcu.edu/WirSelfInst/neuro_medStudents/dementias.html

yasasiihitogomi: Ecthyma gangrenosum. Ecthyma gangrenosum is a...

Sat, 15 Jun 2013 14:24:30 +0100

yasasiihitogomi:

Ecthyma gangrenosum.

Ecthyma gangrenosum is a well recognized cutaneous manifestation of severe, invasive infection by Pseudomonas aeruginosa that is usually seen in immunocompromised and critically ill patients.

stellar-indulgence: mouse dorsal root ganglion

Sat, 15 Jun 2013 09:36:23 +0100

stellar-indulgence:

mouse dorsal root ganglion

stellar-indulgence: Primary neuronal cultures stained for...

Sat, 15 Jun 2013 04:48:25 +0100

stellar-indulgence:

Primary neuronal cultures stained for Bornavirus antigens and Tetanus toxin. LSM 710, Caroline Charlier and Daniel Dunia, CPTP Toulouse, France.

melodiebenford: WHOI microbiologist Stefan Sievert and...

Fri, 14 Jun 2013 19:12:35 +0100

melodiebenford:

WHOI microbiologist Stefan Sievert and colleagues used FISH, or Fluorescence In Situ Hybridization, to localize and identify the microbes living in different parts of the gill chambers of shrimp living near hydrothermal vents.

This image shows two kinds of bacteria attached to a hair-like structure called a seta on the mouth appendages of the shrimp Rimicaris exoculata. The ring-shaped seta (seen here in cross-section) appears blue. Short, thin Gammaproteobacteria appear red, and longer, stouter Epsilonproteobacteria appear green.

Image by Jillian Petersen, Symbiosis Group, Max-Planck-Institute for Marine Microbiology, Bremen, Germany

heythereuniverse: HIV-infected H9 T Cell | NIAID

Thu, 13 Jun 2013 09:36:34 +0100

heythereuniverse:

HIV-infected H9 T Cell | NIAID

fuckyeahneuroscience: Internal Hydrocephalus (by...

Thu, 13 Jun 2013 04:48:23 +0100

fuckyeahneuroscience:

Internal Hydrocephalus (by voxel123)

Obstructive internal hydrocephalus due to aqueduct stenosis (triventricular hydrocephalus).
Note the left sided sinusitis.
Volume Rendering of an MRI scan.

Stereo pair to be viewed in crossview technique.

Rendering done with a Carestream workstation.

Hydrocephalus is a condition in which too much cerebrospinal fluid (CSF) accumulates in the brain’s ventricles, the “open” spaces within the brain through which CSF flows. There are several different types of the condition, each of which can occur as a developmental disorder at infancy or due to some other obstruction of CSF flow such as a tumour or infection.

The pressure build up caused by hydrocephalus can result in severe brain damage and symptoms ranging from headaches to seizures, or even cause death.

The condition can be treated with the insertion of a shunt to drain CSF regularly but shunts must be replaced with age and can themselves cause infection.

Notably, one man lived well into middle-age before understanding how severe his case of childhood hydrocephalus was. In fact, the CSF build up was so severe and ventricles so enlarged, his MRI scans indicated he hardly had any brain tissue at all.

medicalschool: Internal Hydrocephalus Obstructive internal...

Wed, 12 Jun 2013 19:12:40 +0100

medicalschool:

Internal Hydrocephalus

Obstructive internal hydrocephalus due to aqueduct stenosis (triventricular hydrocephalus). Note the left sided sinusitis. Volume Rendering of an MRI scan.

medicineisnotmerchandise: Hyaline and hyperplastic...

Wed, 12 Jun 2013 14:24:31 +0100

medicineisnotmerchandise:

Hyaline and hyperplastic arteriolosclerosis.

Hyaline arteriosclerosis, showing hyaline deposition in the intima and media. In essential hypertension or diabetes mellitus.

Hyperplastic arteriolosclerosis, showing concentric proliferation “onion skinning” of smooth muscle cells in the vessel wall. In malignant hypertension.

wildcat2030: Eyeball discovery may mean safer...

Wed, 12 Jun 2013 09:36:29 +0100

wildcat2030:

Eyeball discovery may mean safer surgery

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Scientists have found a previously undetected layer in the cornea, the clear window at the front of the human eye.

The breakthrough, announced in the journal Ophthalmology, could help surgeons to dramatically improve outcomes for patients undergoing corneal grafts and transplants.

“This is a major discovery that will mean that ophthalmology textbooks will literally need to be re-written. Having identified this new and distinct layer deep in the tissue of the cornea, we can now exploit its presence to make operations much safer and simpler for patients,” says Harminder Dua, professor of ophthalmology and visual sciences at the University of Nottingham, for whom the new layer has been named.

“From a clinical perspective, there are many diseases that affect the back of the cornea which clinicians across the world are already beginning to relate to the presence, absence or tear in this layer.”

The human cornea is the clear protective lens on the front of the eye through which light enters the eye. Scientists previously believed the cornea to be comprised of five layers, from front to back, the corneal epithelium, Bowman’s layer, the corneal stroma, Descemet’s membrane, and the corneal endothelium.

The new layer that has been discovered is located at the back of the cornea between the corneal stroma and Descemet’s membrane. Although it is just 15 microns thick—the entire cornea is around 550 microns thick or 0.5mm—it is incredibly tough and is strong enough to be able to withstand one and a half to two bars of pressure.

the-science-llama: Top Pharmaceutical Products by US Retail...

Wed, 12 Jun 2013 04:48:32 +0100

Pharmaceutical Products Posters by the Njardarson Group (University of Arizona) // posted by The-Science-Llama

Pharmaceutical Products Posters by the Njardarson Group (University of Arizona) // posted by The-Science-Llama

the-science-llama:

Top Pharmaceutical Products by US Retail Sales in 2011

Compiled and Produced by the Njardarson Group (The University of Arizona): Edon Vitaku, Elizabeth A. Ilardi, Jon T. Njardarson

See the rest here along with many other Diseased Focused Pharmaceuticals.

frontal-cortex: Mouse embryo vertebral column (dorsal view),...

Mon, 10 Jun 2013 17:28:43 +0100

frontal-cortex:

Mouse embryo vertebral column (dorsal view), stained for bone (Alizarin red), and cartilage (Alcian blue). (kusumi.lab.asu.edu)

jtotheizzoe: Wee Yeasty Beasties Fungi are like Rodney...

Thu, 06 Jun 2013 19:12:22 +0100

jtotheizzoe:

Wee Yeasty Beasties

Fungi are like Rodney Dangerfields of the microbial world. Funny looking, often oddly round, and they get no respect.

I mean, their name suggests that they’d be rather enjoyable to hang out with*. A new survey of the human skin ecosystem has identified some of their diverse influence on human health and biology.

For as much attention as our microbiome gets these days (need a microbiome introduction? I made a video about it), the bacteria receive most of the publicity. But as the photo above shows, many regions of our bodies are teeming with yeast and other fungi (the blue dots are yeast on a human hair). Understanding their diversity is essential to figuring out who’s a good fungi and who’s a yeast beast.

Not only is it important to understand how these various species lead to medical annoyances like toenail infections, athlete’s foot, dandruff, diaper rash, and, of course, yeast infections, but also how they interact with or are held in check by our bacterial copilots. With as many as 60 to 80 different species living on your feet, who’s welcome and who’s a ticking time bomb for a locker-room itch-fest?

Read more at NPR or check out the original research in Nature.

*That’s a “fun guy” joke. I hope you got it. Not the fungus. The joke.

Neuroscience: Depression Linked to Telomere Enzyme, Aging, Chronic Disease

Wed, 05 Jun 2013 19:12:29 +0100

Neuroscience: Depression Linked to Telomere Enzyme, Aging, Chronic Disease:

neurosciencestuff:

The first symptoms of major depression may be behavioral, but the common mental illness is based in biology — and not limited to the brain.

In recent years, some studies have linked major, long-term depression with life-threatening chronic disease and with earlier death, even after lifestyle risk factors have been taken into account.

Now a research team led by Owen Wolkowitz, MD, professor of psychiatry at UC San Francisco, has found that within cells of the immune system, activity of an enzyme called telomerase is greater, on average, in untreated individuals with major depression. The preliminary findings from his latest, ongoing study was reported Wednesday at the annual meeting of the American Psychiatric Association in San Francisco.

Telomerase is an enzyme that lengthens protective end caps on the chromosomes’ DNA, called telomeres. Shortened telomeres have been associated with earlier death and with chronic diseases in population studies.

The heightened telomerase activity in untreated major depression might represent the body’s attempt to fight back against the progression of disease, in order to prevent biological damage in long-depressed individuals, Wolkowitz said.

The researchers made another discovery that may suggest a protective role for telomerase. Using magnetic resonance imaging (MRI), they found that, in untreated, depressed study participants, the size of the hippocampus, a brain structure that is critical for learning and memory, was associated with the amount of telomerase activity measured in the white blood cells. Such an association at a single point in time cannot be used to conclude that there is a cause-and-effect relationship with telomerase helping to protect the hippocampus, but it is plausible, Wolkowitz said.

Telomerase Activity and Antidepressants

Remarkably, the researchers also found that the enzyme’s activity went up when some patients began taking an antidepressant. In fact, depressed participants with lower telomerase activity at baseline — as well as those in whom enzyme activity increased the most with treatment — were the most likely to become less depressed with treatment.

“Our results are consistent with the beneficial effect of telomerase when it is boosted in animal studies, where it has been associated with the growth of new nerve cells in the hippocampus and with antidepressant-like effects, evidenced by increased exploratory behavior,” Wolkowitz said. He cautions that his new findings are preliminary due to the small size of the study and must be confirmed through further research.

The researchers also measured telomere length in the same immune cells. Only very chronically depressed individuals showed telomere shortening, Wolkowitz said.

“The longer people had been depressed, the shorter their telomeres were,” he said. “Shortened telomere length has been previously demonstrated in major depression in most, but not all, studies that have examined it. The duration of depression may be a critical factor.”

Ongoing Study

The 20 depressed participants enrolled in the study had been untreated for at least six weeks and had an average lifetime duration of depression of about 13 years. After baseline evaluation and laboratory measures, 16 of the depressed participants were treated with sertraline, a member of the most popular class of antidepressants, the serotonin-selective-reuptake-inhibitors (SSRIs), and then evaluated again after eight weeks. There were 20 healthy participants who served as controls.

The ongoing study still is accepting depressed participants who are not now taking antidepressants.

Wolkowitz’s team also studies chronic inflammation and the biochemical phenomenon of oxidative stress, which he said have often been reported in major depression. Wolkowitz is exploring the hypothesis that inflammation and oxidative stress play a role in telomere shortening and accelerated aging in depression.

“New insights into the mechanisms of these processes may well lead to new treatments — both pharmacological and behavioral — that will be distinctly different from the current generation of drugs prescribed to treat depression,” he said. “Additional studies might lead to simple blood tests that can measure accelerated immune-cell aging.”

medicalschool: Histology of the human eye

Wed, 05 Jun 2013 14:24:39 +0100

medicalschool:

Histology of the human eye

medicineisnotmerchandise: PIP2 secondary message system

Wed, 05 Jun 2013 09:36:24 +0100

medicineisnotmerchandise:

PIP2 secondary message system

Photo

Wed, 05 Jun 2013 04:48:25 +0100

Chagas Disease is the 'new AIDS of the Americas'

Tue, 04 Jun 2013 19:12:19 +0100

ziyadmd:

A little-known life-threatening illness caused by blood sucking insects has been labelled the ‘new AIDS of the Americas’ by experts. The parasitic illness called Chagas Disease has similarities to the early spread of HIV, according to a new study.

Read More